This invention relates to a method and an apparatus for testing true/false property of various cards such as bill, coin, ID card, credit card, bank card, check card and composite card, etc., and card or the like on which information is recorded such as passenger ticket, etc., and more particularly to a true/false testing method for bill to be tested and a true/false testing apparatus for bill to be tested so as to have ability of testing, in a non-contact manner, bill to be tested printed by magnetic ink.
In recent years, with popularization of the automatic vending machine, etc., there is no end to mischief to deceive unit such as bill discriminator, etc. to snatch change within the unit, etc. Moreover, crimes by forgery of bill are being increased. Further, there are being increased the cases where foreign bills are taken in from various foreign countries followed by internalization, and those foreign bills are intentionally or erroneously used in the automatic vendering machine, etc.
From such situations, a measure by realization of high level printing of bill is taken and improvement in the security and testing technology of high accuracy are required for the unit.
As one of realization of high level printing of bill, a method using magnetic ink is known. For example, there is one dollar bill of U.S.A., etc. printed by magnetic ink. In the case of this one dollar bill, the strength of residual magnetism in space spaced by about 1 mm from the surface thereof is about 10xe2x88x924 Oe (Oersted) to 10xe2x88x923 Oe (Oersted). This corresponds to intensity (strength) of {fraction (1/100)} to {fraction (1/1000)} of ground magnetism.
In the unit of the prior art, a method using magnetic head is typical as a method of detecting magnetic ink. Further, in the magnetic head of the conventional unit, coil type magnetic head adapted so that coil is wound on magnetic pole by magnetic material, and MR element type magnetic head using magnetic resistance (MR) element, etc. are used. Even magnetic head of the MR element type of relatively high sensitivity among these both magnetic heads has its sensitivity of about 10xe2x88x922 Oe (Oersted).
As stated above, in the conventional bill discriminating machine, because the sensitivity of the magnetic head is low, it was required for detecting magnetism of the magnetic ink portion of the bill surface to carry out scanning while allowing the magnetic head to be in contact with the printing portion of magnetic ink. As a result, since stripe when the magnetic head portion is scanned is left on the surface of the bill, which portion of bill is detected by the unit becomes clear. This is suitable target for person who tries to intentionally carry out mischief, and there is the problem in the security serving as clue to deceive the unit or the like.
On the other hand, since bill is carried in the state where it is put between the magnetic head and the roller as described above, there was also the problem that bill is easy to be clogged at the magnetic head portion of the carrying path. Further, since bill is carried in the state in contact with the magnetic head portion, there were problems that mechanical abrasion of the magnetic head takes place, and life time of the magnetic head is shortened and life time of the bill is shortened. In addition, since scanning is carried out in the state where the magnetic head and the roller are caused to be in contact with the bill, there took place the problem that dust is apt to be attached to the magnetic head, and a predetermined singal cannot be obtained in the remarkable case.
In view of the above, as a way of use of the magnetic head of the conventional type, the magnetic head is caused to be in contact with the magnetic ink portion printed on the bill surface to carry out scanning in such a manner that the bill is put between the magnetic head and the roller in order to further ensure contact between the bill and the magnetic head to carry out test from signal obtained at that time whether or not bill to be tested is true.
Moreover, in the case of testing the coin, as true/false test of coin, many kinds of methods are proposed as compared to the bill. There are, e.g., a method in which coin dimension such as diameter or thickness, etc. is caused to be reference, a method in which hole with respect to the coin having hole is caused to be reference, a method in which notches of outer circumference are caused to be reference, a method in which projected edge with respect to coin provided with projected edge is caused to be reference, and a method in which coin material property such as weight, sound, mechanical repulsive property, or electromagnetic absorption, etc. is caused to be reference, etc. This is because, in the case of coin, there are many kinds of coins in both shape and material entirely unlike money in which shape and material are substantially fixed such as bill.
In this case, when consideration is made in connection with the automatic vending machine in which it is common to provide true/false testing means for coin, it is necessary that both bill and coin can be similarly tested. In view of the above, even in test of coin, it is desirable to adopt testing technique of bill even if any method can be utilized in addition to the testing technique of coin.
In view of the above, an object of this invention is to provide a true/false property testing method for bill to be tested and a true/false property testing apparatus for bill to be tested capable of testing, in a non-contact manner, true/false property of bill to be tested in order to improve the security and to prevent wear of bill and testing apparatus.
Moreover, an object of this invention is to provide a reading method and a reading apparatus for magnetic card or the like capable of improving the security and preventing wear of the magnetic card or the like, thus making it possible to read, in non-contact manner, recording information of magnetic card or the like.
Further, an object of this invention is to provide a true/false property testing method for coin and a true/false property testing apparatus for coin capable of carrying out, with high accuracy, true/false test of coin by magnetic detecting means.
In order to attain the above-described objects, this invention is characterized in that, in a method of testing, in a non-contact manner, true/false property of bill to be tested, a non-contact type magnetic sensor is disposed, at a predetermined position of a carrying path of bill, in a manner close to the carrying path to test true/false property of the bill on the basis of a signal outputted from the magnetic sensor according as the bill is carried along the carrying path.
Moreover, in accordance with this invention, in an apparatus for testing, in a non-contact manner, true/false property of bill to be tested, there may be employed a configuration comprising a thin film flux gate type magnetic sensor disposed, at a predetermined position of a carrying path of the bill, in a manner close to the carrying path, and testing means for testing true/false property of the bill on the basis of a signal outputted from the magnetic sensor according as the bill is carried along the carrying path.
Further, in accordance with this invention, in a method of carrying out, in the middle of carrying of coin to be tested, magnetic detection from the coin while applying excitation magnetic field to the coin to test its true/false property, when the magnetic detection is carried out, a signal with respect to time change of circumferential magnetic flux produced by allowing high frequency current to flow in a magnetic line is taken out as change by the excitation magnetic field.
Further, in accordance with this invention, in a method of reading, by the non-contact system, information recorded while carrying magnetic card or the like for recording information by magnetism along a carrying path, a magnetic sensor is disposed, at a predetermined position of the carrying path of the magnetic card or the like, in a manner close to the carrying path to read information recorded on the magnetic card or the like on the basis of a signal outputted from the magnetic sensor according as the magnetic card or the like is carried along the carrying path.
In addition, the magnetic sensor may be constituted by a magnetic inductance type magnetic sensor for detecting voltage with respect to time change of circumferential magnetic flux produced by allowing current varying in point of time to flow in the magnetic line as change by externally applied magnetic field to read information recorded on bill, coin or magnetic card or the like to be tested on the basis of a signal outputted from the magnetic inductance type magnetic sensor.